Multiscale Modeling of Solid Electrolyte Interphase Formation on Oxygen-Functionalized Graphite Anodes for Lithium-Ion Batteries

The solid electrolyte interphase (SEI) plays a crucial regulatory role in the electrochemical reversibility of lithium-ion batteries, yet understanding of its formation mechanism remains limited due to compositional complexity. By integrating a multiscale simulation framework combining density functional theory (DFT), molecular dynamics (MD) and the REACTER protocol, which dynamically updates molecular topologies to simulate bond-breaking and formation in fixed-valence force fields, enhanced with topology-mapped reaction templates and physics-informed constraints, we elucidate the atomistic mechanisms governing the initial formation of the SEI on pristine and functionalized graphite anodes (O-terminated, OH-terminated, and O/OH-terminated). Simulation results reveal that functionalized graphite surfaces universally exhibit three-stage SEI growth kinetics: rapid initial formation, transition regulation, and steady-state growth phases. A key finding reveals that OH-terminated surfaces accelerate the formation of thin but densely structured inorganic/organic composite SEI layers, which effectively suppress component dissolution into the electrolyte. This optimized interface exhibits superior transport properties within the interfacial region between the SEI and the electrolyte, demonstrating enhanced ionic conductivity and favorable viscosity characteristics. Our multiscale analysis highlights electrode surface functionalization as a highly promising strategy for controlling SEI growth mechanisms, providing fundamental principles for the rational design of high-performance battery interfaces.